Detachable tool holder, especially for grooving files



ANN ET AL 2,917,813

Dec. 22, 1959 H. ACKERM ECIALLY FOR GROOVING FILES DETACHABLE TOOLHOLDER, ESP

Filed April 10, 1958 wmvra/es H Ac/germann Crummenerl ATTKS.

2,917,813 DETACHABLE TOOL HOLDER, ESPECIALLY FOR GROOVING FILES HugoAckermann and Gerhard Criimmenerl, Kierspe,

Germany, assignors to Hugo Ackermann, Kierspe,

Westphalia, Germany Application April 10, 1958, Serial No. 727,729Claims priority, application Germany August 2, 1957 2 Claims. (Cl.29-80) This invention relates to tool holders or grasps, and morespecifically to a tool holder, especially for grooving files and similartools, which can be readily attached to and detached from such a tooland which provides a simple means for a workman for securely holding thetool without running the risk of being injured during the use thereof.

Grooving files, which have an intermediate shaft portion of square orrectangular cross section and ends curved in opposite directions andconstituting the actual filing means, are generally open to theobjection that the workman holding one end of the file with his barehand can be easily injured by said end and that the file does not permitto be grasped with the hand as securely and firmly as would be necessaryfor the work.

To overcome this objection, it is the object of the present invention toprovide a simple holder for grooving files and similar tools, whichholder is made in one piece and has a straight intermediate portion, twoprojections spaced in the longitudinal direction of the holder at oneend thereof, and a substantially hemispherical portion at the other endof the holder. The two projections are provided with slots extendingfrom opposite lateral sides thereof and the inner side of thehemispherical portion has a number of parallel grooves formed therein.To attach a file to the holder, the file is inserted with its one end inthe tWo slots in said projections and passed therethrough until said endcontacts the inner side of the hemispherical portion. A slight pressureexerted on said end of the file will cause it to engage in one of thegrooves in the hemispherical portion and to be securely held therein byits intrinsic tension. The file may at any time be detached from theholder by the same manipulations applied in reversed order.

A preferred embodiment of the invention is illustrated by way of examplein the accompanying drawing in which:

Fig. l is a side view of a tool holder according to the invention with agrooving file clamped therein;

Fig. 2 is a front view of the same tool holder but with the fileremoved;

Fig. 3 is a top plan view of Fig. 2, and

Fig. 4 is a fragmentary rear view of Fig. l.

The drawing illustrates a holder or grasp for receiving a tool and whichis especially adapted for use with a grooving file g having asubstantially straight shank portion and ends h and h curved in oppositedirections as shown in Fig. 1.

The holder is made in one piece from metal or a synthetic material suchas thermoplastic material or thermosetting plastics and consists of astraight elongated intermediate portion a, two projections b and formedat one end thereof and spaced in the longitudinal direction of saidintermediate portion a, and a substantially hemispherical portion j atthe other end of said intermediate portion a. The projections b and cand the hemispherical portion j extend in the same direction from oneside of the holder and substantially normal to the longitudinal axisthereof. Slots d and e are formed in the projections b and c in such amanner that the slot d in the projection b extends from one side thereofand terminates short of the opposite side of the projection b, Whereasnited States Patent the slot e in the projection 0 extends from thatside which is adjacent said opposite side of the projection b andterminates short of the side which is adjacent said one side of theprojection b. As can be seen from Figs. 2 and 3, the slots d and eregister with each other only at their inner ends in the middle of theprojections b and c which, in top plan view, are substantially U-shaped.As shown in Fig. 4, the slots d and e extend in a common plane passingthrough the projections b and c at a slight incline with respect to theplane normal to the projections b and c and in which the portion aextends.

To attach the file g to the holder, the shank portion 1 of the file isintroduced laterally in the slot e in the projection c and then in theslot at in the projection b. The file is then slipped through the slotsd and e until its end h contacts the inner side of the hemisphericalportion j which is provided with a plurality of serrations or grooves 1.By pressing the end h of the file toward the intermediate portion a andat the same time toward the hemispherical portion of the holder, the endh engages in one of the grooves i and is securely held therein by itsintrinsic tension. The file can then be used in the usual manner for thetype of work it is destined for, the workman gripping the holder withits hemispherical portion resting snugly in the palm of his hand. Whenit is desired to detach the file from the holder, this can be readilyaccomplished by again pressing the end I: of the file toward theintermediate portion a of the holder, thereby causing the end 11 todisengage from the respective groove i, whereupon the file can beremoved from the holder and, if desired, another file may be inserted inthe same manner as hereinbefore described.

From the foregoing description it will be apparent that the tool holderproposed by the present invention afi'ords a simple means for securelyholding a tool, especially a grooving file, and reliably preventing eachworkman from being injured when using such a file.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description and all changeswhich come within the meaning and range of equivalency of the claims aretherefore intended to be embraced therein.

We claim:

1. A detachable tool holder, especially for grooving files and similartools, comprising in combination a substantially straight elongatedintermediate portion, two projections formed at one end thereof andspaced in the longitudinal direction of said intermediate portion, asubstantially hemispherical portion at the other end of saidintermediate portion to form an abutment for one end of a tool, saidprojections and said hemispherical portion extending in the samedirection from one side of the intermediate portion and substantiallynormal to the longitudinal axis thereof, a slot in each projection, saidslots extending from opposite sides of the projections and terminatingshort of the opposite side of each projection, and a number of parallelgrooves formed on the hemispherical portion for tensioning a toolmounted in the holder.

2. A tool holder as claimed in claim 1, wherein the slots extend in acommon plane passing through the projections at a slight incline withrespect to the plane normal'to the projections and in which theelongated intermediate portion extends.

References Cited in the file of this patent UNITED STATES PATENTS359,400 Mosher Mar. 15, 1887

